A novel angle on helical blade placement in trochanteric fractures – The axis-blade angle. Issue 7 (July 2019)

• Record Type: Journal Article
• Authors: Mao, Wei; He, Yi-Qun; Tang, Han; Chen, Xu-Jun; Li, Lin-Li; Dong, You-Hai
• Is Part Of: Injury. Volume 50:Issue 7(2019)
• Page Start: 1333
• Page End: 1338
• Publication Date: 2019-07
• Subjects: Trochanteric fractures -- Helical blade -- Axis-blade angle; Wounds and injuries -- Surgery -- Periodicals; Accidents -- Periodicals; Wounds and Injuries -- surgery -- Periodicals; Lésions et blessures -- Chirurgie -- Périodiques; Electronic journals; Electronic journals; 617.1
• DOI: 10.1016/j.injury.2019.05.006
• Languages: English
• ISSNs: 0020-1383

Abstract

Highlights: The current study proposed a new measurement method for helical blade placement and investigated its clinical applicability. The ABA complements the TAD (or the CalTAD) and provides instruction for the intraoperative adjustment of the guide wire direction. Placing the helical blade with an ABA > −10° can effectively reduce the risk of mechanical complications. Abstract: Introduction: For trochanteric fractures, helical blade placement is crucial to the prognosis of operations. Existing measurement methods used for blade placement include the Cleveland zone, the tip-apex distance (TAD), the calcar-referenced tip-apex distance (CalTAD), and the Parker's ratio. These methods all lack a direct view on blade direction. The current study proposed the axis-blade angle (ABA) to solve direction problem and investigated its clinical applicability. Methods: A retrospective study collected 156 patients between May 2014 and February 2018. The occurrence of mechanical complications was analyzed in relation to age, gender, fracture side, American Society of Anesthesiologists classification, fracture classification, reduction quality, bone quality, the Cleveland zone, the Parker's ratio, the TAD, the CalTAD, and the ABA. Results: 119 patients, including 25 with mechanical complications, were suitable for full analysis. In the univariate analysis, the Cleveland zone, reduction quality, the TAD, the CalTAD and the ABA were statistically associated with mechanical complications. In the multivariate analysis, reduction quality (p = 0.008) and the ABA (p < 0.001; adjusted OR 0.86;95% CI 0.77 to 0.96) showed significant results, which indicated that reduction quality and the ABA were two independent influencing factors for mechanical complications. Calculation of the receiver operating characteristic (ROC) curve indicated that the ABA was a reliable predictor of mechanical complications at the cut-off of −10°. Conclusions: The ABA provides instruction for the intraoperative adjustment of guide wire direction. Placing the helical blade with an ABA > −10° can effectively reduce the risk of mechanical complications.